JSFiddle - React, Tailwind, and code Playground
by painotpi
HTML
<img src='http://1.bp.blogspot.com/-SaHnF4huNdM/ULNGwjgMVvI/AAAAAAAADJk/uKmkDnYZpfc/s200/jerry+mouse.jpg' alt='' />
<div>
</div>
<section>
</section>
CSS
img{
display: none;
}
JavaScript
var down = false;
var img = $('img');
var canvas = document.createElement("canvas");
canvas.width = img.width();
canvas.height = img.height();
canvas.getContext('2d').drawImage(img[0], 0, 0);
$('section').append(canvas);
img
.mousedown(function(){
down = true;
})
.mouseup(function(){
down = false;
})
.mouseleave(function(){
down = false;
})
.mousemove(function(e){
if(down){
var x = $('div').html();
$('div').html(x + ' ' + e.clientX + ", " + e.clientY);
}
});
img.on('dragstart', function(e){
e.preventDefault();
return false;
});
$('section').on('click', 'canvas', function(e){
alert(canvas.getContext('2d').getImageData(e.clientX, e.clientY, 1, 1).data)
});